Search

The merger of two neutron stars is predicted to give rise to three major detectable phenomena: a short burst of γ-rays, a gravitational-wave signal, and a transient optical–near-infrared source powered by the synthesis of large amounts of very heavy elements via rapid neutron capture (the r-process). Such transients, named ‘macronovae’ or ‘kilonovae’, are believed to be centres of production of rare elements such as gold and platinum. The most compelling evidence so far for a kilonova was a very faint near-infrared rebrightening in the afterglow of a short γ-ray burst at redshift z = 0.356, although findings indicating bluer events have been reported. Here we report the spectral identification and describe the physical properties of a bright kilonova associated with the gravitational-wave source GW170817 and γ-ray burst GRB 170817A associated with a galaxy at a distance of 40 megaparsecs from Earth. Using a series of spectra from ground-based observatories covering the wavelength range from the ultraviolet to the near-infrared, we find that the kilonova is characterized by rapidly expanding ejecta with spectral features similar to those predicted by current models. The ejecta is optically thick early on, with a velocity of about 0.2 times light speed, and reaches a radius of about 50 astronomical units in only 1.5 days. As the ejecta expands, broad absorption-like lines appear on the spectral continuum, indicating atomic species produced by nucleosynthesis that occurs in the post-merger fast-moving dynamical ejecta and in two slower (0.05 times light speed) wind regions. Comparison with spectral models suggests that the merger ejected 0.03 to 0.05 solar masses of material, including high-opacity lanthanides.

Aims. With an observed and rest-frame duration of <2 s and <0.5 s, respectively, GRB 090426 could be classified as a short GRB. The prompt detection, both from space and ground-based telescopes, of a bright optical counterpart to this GRB offered a unique opportunity to complete a detailed study.

The long and relatively faint gamma-ray burst GRB 060605 detected by Swift/BAT lasted about 20 s. Its afterglow could be observed with Swift/XRT for nearly 1 day, while Swift/UVOT could detect the afterglow during the first 6 h after the event. Here, we report on integral field spectroscopy of its afterglow performed with PMAS/PPak mounted at the Calar Alto 3.5 m telescope. In addition, we report on a detailed analysis of XRT and UVOT data and on the results of deep late-time VLT observations that reveal the GRB host galaxy. We find that the burst occurred at a redshift of $z = 3.773$, possibly associated with a faint, RC= 26.4 ±0.3 host. Based on the optical and X-ray data, we deduce information on the SED of the afterglow, the position of the cooling frequency in the SED, the nature of the circumburst environment, its collimation factor, and its energetics. We find that the GRB fireball was expanding into a constant-density medium and that the explosion was collimated with a narrow half-opening angle of about 2.4 degrees. The initial Lorentz factor of the fireball was about 250; however, its beaming-corrected energy release in the gamma-ray band was comparably low. The optical, X-ray afterglow, on the other hand, was rather luminous. Finally, we find that the data are consistent within the error bars with an achromatic evolution of the afterglow during the suspected jet break time at about 0.27 days after the burst.

We present results of several pointed X-ray broad band observations of the “symbiotic X-ray binary” 4U 1954+31 performed with the satellites BeppoSAX, EXOSAT, ROSAT, RXTEand Swiftbetween October 1983 and April 2006. We also studied the RXTEASM data over a period of more than 10 years, from January 1996 to October 2006. Light curves of all pointed observations show an erratic behaviour with sudden increases in the source emission on timescales variable from hundreds to thousands of seconds. There are no indications of changes in the source spectral hardness, with the possible exception of the RXTEpointed observation. Timing analysis does not reveal the presence of coherent pulsations or periodicities either in the pointed observations in the range from 2 ms to 2000 s or in the long-term RXTEASM light curve on timescales from days to years. The 0.2-150 keV spectrum, obtained with BeppoSAX, is the widest for this source available to date in terms of spectral coverage and is well described by a model consisting of a lower-energy thermal component (hot diffuse gas) plus a higher-energy (Comptonization) emission, with the latter modified by a partially-covering cold absorber plus a warm (ionized) absorber. A blackbody modelization of our BeppoSAXlow-energy data is ruled out. The presence of a complex absorber local to the source is also supported by the 0.1-2 keV ROSATspectrum. RXTE, EXOSATand SwiftX-ray spectroscopy is consistent with the above results, but indicates variations in the density and the ionization of the local absorber. A 6.5 keV iron emission line is possibly detected in the BeppoSAXand RXTEspectra. All this information suggests that the scenario that better describes 4U 1954+31 consists of a binary system in which a neutron star orbits in a highly inhomogeneus medium, accreting matter from a stellar wind coming from its optical companion, an M-type giant star.

We analyze and discuss the position of GRB 060218 and GRB 060614 in the $E_{\rm p,i} - E_{\rm iso}$plane. GRB 060218 is important because of its similarity with GRB 980425, the prototypical event of the GRB–SN connection. While GRB 980425 is an outlier of the $E_{\rm p,i} - E_{\rm iso}$correlation, we find that GRB 060218 is fully consistent with it. This evidence, combined with the “chromatic” behavior of the afterglow light curves, is at odds with the hypothesis that GRB 060218 was a “standard” GRB seen off-axis and supports the existence of a class of truly sub-energetic GRBs. GRB 060614 is a peculiar event not accompanied by a bright supernova. Based on published spectral information, we find that also this event is consistent with the $E_{\rm p,i} - E_{\rm iso}$correlation. We discuss the implications of our results for the rate of sub-energetic GRBs, the GRB/SN connection and the properties of the newly discovered sub-class of long GRBs not associated with bright supernovae. We have included in our analysis other recent GRBs with clear evidence (or clear evidence of lack) of associated SNe.

We present the catalog of X-ray afterglow observed by BeppoSAX from the launch of the satellite to the end of the mission. Thirty-three X-ray afterglows out of 39 observations were securely identified based on their fading behavior. We have extracted the continuum parameters (decay index, spectral index, flux, absorption) for all available afterglows. We point out a possible correlation between the X-ray afterglow luminosity and the energy emitted during the prompt γ-ray event. We do not detect a significant jet signature within the afterglows, implying a lower limit on the beaming angle, nor a standard energy release when X-ray fluxes are corrected for beaming. Our data support the hypothesis that the burst should be surrounded by an interstellar medium rather than a wind environment, and that this environment should be dense. This may be explained by a termination shock located near the burst progenitor. We finally point out that some dark bursts may be explained by an intrinsic faintness of the event, while others may be strongly absorbed.

Aims.To investigate the physical nature of the afterglow emission. We report on the photometric, spectroscopic and polarimetric observations of the optical afterglow of Gamma–Ray Burst (GRB) 030328 detected by HETE-2.

We observed with Chandratwo peculiar galactic X-ray sources, 4U 1700+24 and 4U 1954+319, which are suspected to have a M-type giant star as optical counterpart, in order to get a high-precision astrometric position for both of them. The peculiarity of these sources lies in the fact that these are the only two cases among low-mass X-ray binaries (LMXBs), besides the confirmed case of GX 1+4, for which the companion can possibly be a M-type giant. We found that in both cases the field M-type giant star is indeed the counterpart of these X-ray sources. We also determined the distance to 4U 1954+319 to be ~1.7 kpc. This result suggests that a number of faint ($L_{\rm X} \sim 10^{32}{-}10^{34}$erg s-1) Galactic X-ray sources are “symbiotic X-ray binaries”, that is, wide-orbit LMXBs composed of a compact object, most likely a neutron star, accreting from the wind of a M-type giant.

A pointed observation of the galactic high-mass X-ray binary 4U 0114+65 was carried out with BeppoSAXto compare the X-ray spectral and timing characteristics observed by this satellite over the broadest range of energies thus far (1.5–100 keV) with the information previously obtained with other spacecraft. The light curve of 4U 0114+65 shows a large flare at the beginning of the BeppoSAXpointing and no significant hardness evolution either during the flare or in the low state occurring after the flare itself. The modulation at ~2.7 h, attributed to the accreting neutron star (NS) spin periodicity, is not significantly detected in our data, although fluctuations with timescales of ~3 h can be seen in the 2–10 keV light curve. Shorter modulations down to timescales of minutes are also found and interpreted as due to accretion of matter onto the NS. The flaring and the low state spectra of 4U 0114+65 can be equally well fitted either with a power law modulated by a high-energy exponential cutoff or with a Comptonization model. During the low state the presence, although tentative, of a thermal component (with $kT \sim 0.3$keV) at low energies, possibly produced by an ionized plasma cloud around the NS, cannot be excluded. Contrary to previous claims, a cyclotron resonant feature in absorption at ~22 keV was not detected in the BeppoSAXspectroscopic data, whereas evidence for a Fe emission line around 6.4 keV is found only during the low state emission. Using all of the above information, a scenario for the system in which the NS is embedded in, and accreting from, a low angular momentum gas cloud is envisaged.

We report on BeppoSAX simultaneous X- and γ-ray observations of the bright γ-ray burst (GRB) 990123. We present the broad-band spectrum of the prompt emission, including optical, X- and γ-rays, confirming the suggestion that the emission mechanisms at low and high frequencies must have different physical origins. In the framework of the standard fireball model, we discuss the X-ray afterglow observed by the Narrow Field Instruments (NFIs) on board BeppoSAX and its hard X-ray emission up to 60 keV several hours after the burst, detected for about 20 ks by the Phoswich Detection System (PDS). Considering the $2{-}10$keV and optical light curves, the $0.1{-}60$keV spectrum during the 20 ks in which the PDS signal was present and the 8.46 GHz upper limits, we find that the multi-wavelength observations cannot be readily accommodated by basic afterglow models. While the temporal and spectral behavior of the optical afterglow is possibly explained by a synchrotron cooling frequency between the optical and the X-ray energy band during the NFIs observations, in X-rays this assumption only accounts for the slope of the $2{-}10$keV light curve, but not for the flatness of the $0.1{-}60$keV spectrum. Including the contribution of Inverse Compton (IC) scattering, we solve the problem of the flat X-ray spectrum and justify the hard X-ray emission; we also suggest that the lack of a significant detection of $15{-}60$keV emission in the following 75 ks and last 70 ks spectra, should be related to poorer statistics rather than to an important suppression of IC contribution. However, considering also the radio band data, we find the 8.46 GHz upper limits violated. On the other hand, leaving unchanged the emission mechanism requires modifying the hydrodynamics by invoking an ambient medium whose density rises rapidly with radius and by having the shock losing energy. Thus we are left with an open puzzle which requires further inspection.

We report on the BeppoSAXdata analysis of the afterglow of Gamma-Ray Burst (GRB) 990123, one of the brightest GRBs detected by BeppoSAX. Mainly due to its exceptional brightness, this is the only source for which the Wide Field Cameras have allowed an early detection of the X-ray afterglow between ~20 and 60 min after the GRB trigger. Besides, again for the first time, high-energy emission from the afterglow was detected up to 60 keV. For the X-ray afterglow we found a power-law decay with index $\alpha = 1.46 \pm 0.04$; the spectrum has a power-law shape with photon index $\Gamma \sim 1.9$. The backward extrapolation of the afterglow decay smoothly reconnects with the late GRB emission, thus suggesting that both emissions are produced by the same phenomenon. An extensive set of multiwavelength observations for the GRB 990123 afterglow made during the BeppoSAXpointing was collected from the literature. The hard X-ray to radio range coverage allowed to construct a spectral flux distribution and to perform an analysis of the GRB afterglow in the context of the “fireball” model. We also report the results of temporal and spectral analysis of an X-ray source serendipitously observed about 22'north of the GRB afterglow, along with the optical spectroscopy of its possible counterpart to establish the nature of this source.

We present the results of an optical and near-infrared (NIR) monitoring campaign of the counterpart of Gamma-Ray Burst (GRB) 000911, located at redshift $z = 1.06$, from 5 days to more than 13 months after explosion. Our extensive dataset is a factor of 2 larger and spans a time interval ~4 times longer than the ones considered previously for this GRB afterglow; this allows a more thorough analysis of its light curve and of the GRB host galaxy properties. The afterglow light curves show a single power-law temporal decline, modified at late times by light from a host galaxy with moderate intrinsic extinction, and possibly by an emerging supernova (SN). The afterglow evolution is interpreted within the classical “fireball” scenario as a weakly collimated adiabatic shock propagating in the interstellar medium. The presence of a SN light curve superimposed on the non-thermal afterglow emission is investigated: while in the optical bands no significant contribution to the total light is found from a SN, the NIR J-band data show an excess which is consistent with a SN as bright as the known hypernova SN1998bw. If the SN interpretation is true, this would be the farthest GRB-associated SN, as well as the farthest core-collapse SN, discovered to date. However, other possible explanations of this NIR excess are also investigated. Finally, we studied the photometric properties of the host, and found that it is likely to be a slightly reddened, subluminous, extreme starburst compact galaxy, with luminosity ~0.1 $L^\star$, an age of ~0.5 Gyr and a specific Star Formation Rate (SFR) of ≈30 $M_\odot$yr-1($L/L^\star$)-1. This is the highest specific SFRvalue for a GRB host inferred from optical/NIR data.

We report on results of two BeppoSAXobservations of the Z source GX 17+2. In both cases the source is in the horizontal branch of the colour-intensity diagram. The persistent continuum can be fit by two-component models consisting of a blackbody plus a Comptonization spectrum. With one of these models, two solutions for the blackbody temperature of both the observed and seed photons for Comptonization are equally accepted by the data. In the first observation, when the source is on the left part of the horizontal branch, we observe a hard tail extending up to 120 keV, while in the second observation, when the source moves towards right in the same branch, the tail is no longer detected. The hard ($\ga$30 keV) X-ray emission can be modeled either by a simple power-law with photon index $\Gamma \sim 2.8$, or assuming Comptonization of ~1 keV soft photons off a hybrid thermal plus non-thermal electron plasma. The spectral index of the non-thermal injected electrons is $p \sim 1.7$. The observation of hard X-ray emission only in the left part of the horizontal branch could be indicative of the presence of a threshold in the accretion rate above which the hard tail disappears. An emission line at 6.7 keV with equivalent width $\sim 30$eV is also found in both observations. We discuss these results and their physical implications.

GRB 020410 is by far the longest γ-ray burst (with a duration of about 1600 s) to have been followed up from the X-ray through the radio regime. Afterglow emission was detected in X-rays and at optical wavelengths whereas no emission was detected at 8 GHz brighter than 120 μJy. The decaying X-ray afterglow, back-extrapolated to 11 h after the burst, had a flux of 7.9 $\times$10-12erg cm-2s-1(2–10 keV); the brightest detected so far. No direct redshift determination is available yet for this GRB, but according to the empirical relationship between the peak energy in the $\nu F_\nu$spectrum and the isotropic energy output, zis constrained in the range 0.9–1.5. The reconstructed optical afterglow light curve implies at least two breaks in the simple power law decay. This may be related to emergence of an SN, or refreshment of the external shock by a variation in the circumstellar medium. Considering the backward extrapolation of the 2–10 keV afterglow decay, the prompt lightcurve variability and its spectral evolution, we conclude that the long duration of this event is due to a prolonged activity of the “central engine”.

We report the results of extensive high-energy observations of the X-ray transient and black hole candidate XTE J1720-318performed with INTEGRAL, XMM-Newton and RXTE. The source, which underwent an X-ray outburst in 2003 January, was observed in February in a spectral state dominated by a soft component with a weak high-energy tail. The XMM-Newton data provided a high column density $N_{{\rm H}}$of 1.2 $\times$1022cm-2which suggests that the source lies at the Galactic Centre distance. The simultaneous RXTE and INTEGRAL Target of Opportunity observations allowed us to measure the weak and steep tail, typical of a black-hole binary in the so-called High/Soft State. We then followed the evolution of the source outburst over several months using the INTEGRAL Galactic Centre survey observations. The source became active again at the end of March: it showed a clear transition towards a much harder state, and then decayed to a quiescent state after April. In the hard state, the source was detected up to 200 keV with a power law index of ~1.9 and a peak luminosity of ~7 $\times$1036erg s-1in the 20–200 keV band, for an assumed distance of 8 kpc. We conclude that XTE J1720-318is indeed a new member of the black hole X-ray novae class which populate our galactic bulge and we discuss its properties in the frame of the spectral models used for transient black hole binaries.

We report on the X-ray observations of the X-ray flash (XRF) which occurred on 2002 April 27, three days before BeppoSAXwas switched off. The event was detected with the BeppoSAXWide Field Cameras but not with the Gamma ray Burst Monitor. A follow-up observation with the BeppoSAXNarrow Field Instruments was soon performed and a candidate afterglow source was discovered. We present the results obtained. We also include the results obtained from the observations of the XRF field with the ChandraX-ray satellite. The spectral analysis of the prompt emission shows that the peak energy of the $EF(E)$spectrum is lower than 5.5 keV, with negligible spectral evolution. The X-ray afterglow spectrum is consistent with a power law model with photon index of ~2, while the 2–10 keV flux fades as a power law with a decay index -1.33. Both these indices are typical of GRBs. A very marginal excess at ~4.5–5 keV is found in the afterglow spectrum measured by BeppoSAX. As for many GRBs, the extrapolation of the 2–10 keV fading law back to the time of the prompt emission is consistent with the X-ray flux measured during the second part of the event. We estimate a possible range of values of the redshift and discuss our results in the light of current models of XRFs.

A pointed observation of the low-luminosity galactic source 4U 2206+54 was carried out in November 1998 with BeppoSAX. The light curve of 4U 2206+54 shows erratic variability on a timescale of ~1 h; neither hardness variations nor time periodicities are detected throughout this 67 ks long observation. Thanks to the wide spectral coverage capabilities of BeppoSAXwe could observe the source X-ray continuum over three energy decades, from 0.6 to 60 keV. The spectrum could be equally well fitted either with a blackbody plus Comptonization or with a high energy cutoff power law. No iron emission around 6.5 keV was detected, while a tentative detection of a cyclotron resonant feature in absorption is presented. Comparison of the present BeppoSAXdata with the information available in the literature for this source suggests that 4U 2206+54 is a close binary system in which a (possibly magnetized) NS is accreting from the companion star wind.

Here we report results of an INTEGRAL-AO1 observation of the X-ray burst and atoll source Ser X-1 performed in May 2003. The object was observed for a total on-source time of 400 ks but nearly 8° off-axis due to its amalgamation with an observation of SS 433, the pointing target source. Ser X-1 has been clearly detected up to 30 keV with unprecedented positional accuracy for high-energy emission. The 20–30 keV light curve showed substantial variability during the observation. Comparison with previous observations indicates that the source was in its high (“banana”) state and displayed a soft spectrum during the INTEGRALpointing. A (non simultaneous) radio-to-γ-rays broad-band spectral energy distribution is also presented for the first time and discussed.

We report on spectral and temporal results of the 40–700 keV observations, obtained with the Gamma-Ray Burst Monitor (GRBM) on board BeppoSAX, of the two large flares from the Soft Gamma-ray Repeater SGR 1900+14 occurred on August 27, 1998 and April 18, 2001. From their intensity, fluence and duration, the first one was classified as “giant” and the second as “intermediate”.The spectral results have been obtained with an improved response function of the GRBM. We find that the two events have similar spectral properties, but different temporal properties. The major difference concerns the time profiles of the light curves, whereas the lack of evidence in the 2001 flare for the erratic time variability found at high frequencies (10–1000 Hz) in the 1998 flare could be ascribed to lower counting statistics. We discuss these results in the light of the magnetar model proposed for SGR sources.

We report on photometric, spectroscopic and polarimetric monitoring of the optical and near-infrared (NIR) afterglow of GRB020405. Ground-based optical observations, performed with 8 different telescopes, started about 1 day after the high-energy prompt event and spanned a period of ~10 days; the addition of archival HST data extended the coverage up to ~150 days after the GRB. We report the first detection of the afterglow in NIR bands. The detection of Balmer and oxygen emission lines in the optical spectrum of the host galaxy indicates that the GRB is located at redshift $z =0.691$. Fe iiand Mg iiabsorption systems are detected at $z= 0.691$and at $z = 0.472$in the afterglow optical spectrum. The latter system is likely caused by absorbing clouds in the galaxy complex located ~2''southwest of the GRB020405 host. Hence, for the first time, the galaxy responsible for an intervening absorption line system in the spectrum of a GRB afterglow is spectroscopically identified. Optical and NIR photometry of the afterglow indicates that, between 1 and 10 days after the GRB, the decay in all bands is consistent with a single power law of index $\alpha = 1.54\pm 0.06$. The late-epoch VLT J-band and HST optical points lie above the extrapolation of this power law, so that a plateau (or “bump") is apparent in the VRIJlight curves at 10–20 days after the GRB. The light curves at epochs later than day ~20 after the GRB are consistent with a power-law decay with index $\alpha' = 1.85\pm 0.15$. While other authors have proposed to reproduce the bump with the template of the supernova (SN) 1998bw, considered the prototypical “hypernova”, we suggest that it can also be modeled with a SN having the same temporal profile as the other proposed hypernova SN2002ap, but 1.3 mag brighter at peak, and located at the GRB redshift. Alternatively, a shock re-energization may be responsible for the rebrightening. A single polarimetric R-band measurement shows that the afterglow is polarized, with $P = 1.5\pm 0.4$% and polarization angle $\theta = 172^{\circ}\pm 8^{\circ}$. Broad-band optical-NIR spectral flux distributions show, in the first days after the GRB, a change of slope across the Jband which we interpret as due to the presence of the electron cooling frequency $\nu_{\rm c}$. The analysis of the multiwavelength spectrum within the standard fireball model suggests that a population of relativistic electrons with index $p \sim 2.7$produces the optical-NIR emission via synchrotron radiation in an adiabatically expanding blastwave, with negligible host galaxy extinction, and the X–rays via Inverse Compton scattering off lower-frequency afterglow photons.

Observations of two unclassified Low Mass X–ray Binaries, X1543–624 and X1556–605, are presented. In the 2–10 keV band the first of the two sources is a factor of two stronger than the other. Both sources do not show X–ray bursts, dips or eclipses in their X–ray light curves. We find that both spectra are described by a two–component model consisting of emission from a cool accretion disk plus a Comptonized blackbody with $kT_{\rm bb}\sim 1.5$keV in a low opacity plasma. The spectrum of X1543–624 hardens from the first to the second observation, when the source slowly moves from right to left in the colour–colour diagram. The spectrum of X1556–605 can also be described by a model consisting of a blackbody plus an unsaturated Comptonization with electron energy $kT_{\rm e} \sim 4$keV. In the first observation, X1543–624 shows evidence of a Fe K emission line at 6.4 keV. Moreover, in both observations, the source spectrum exhibits an emission feature around 0.7 keV, which is interpreted as due to the superposition of the K edge absorption features of O and Ne elements with uncommon relative abundances with respect to the solar one (O/O$_{\odot} \sim 0.3$, Ne/Ne$_{\odot} \sim 2.5$). In the spectrum of X1556–605 no emission lines are observed. We discuss these results and their implications for the source classification and the accretion geometry of the compact object.

We report on the prompt and afterglow emission observations of the dark burst GRB010214 with BeppoSAX. The prompt emission shows possible evidence of variable absorption from $N_{\rm H} = 3.0^{+5.1}_{-2.0} \times 10^{23}$cm-2in the first 6 s of the event to a value consistent with the Galactic column density ($N_{\rm H}^{\rm G} = 2.66\times 10^{20}$cm-2) in the GRB direction. An X–ray afterglow emission in the 2–10 keV energy band was detected with BeppoSAX, but an analogue search at lower wavelengths (optical, IR and radio) was unsuccessful. The X–ray afterglow spectrum is consistent with a power–law with Galactic absorption. The light curve shows a complex decay, if the tail of the prompt emission is assumed as the onset of the afterglow: if the origin of the afterglow is coincident with the GRB onset, a bump before ~$3\times10^4$s is inferred, while if the afterglow is assumed to start later, a steepening of the power–law light curve at $t\sim 3\times10^4$s is deduced. We discuss these results in the light of the current models of afterglows and the possible origin of the GRB darkness. Finally, we tentatively derive an estimate of the burst redshift.

We present the main results of a study of spectral and energetics properties of twelve gamma-ray bursts (GRBs) with redshift estimates. All GRBs in our sample were detected by BeppoSAX in a broad energy range (2–700 $\rm keV$). From the redshift estimates and the good-quality BeppoSAX time–integrated spectra we deduce the main properties of GRBs in their cosmological rest frames. All spectra in our sample are satisfactorily represented by the Band model, with no significant soft X–ray excesses or spectral absorptions. We find a positive correlation between the estimated total (isotropic) energies in the 1–10 000 $\rm keV$energy range (Erad) and redshifts z. Interestingly, more luminous GRBs are characterized also by larger peak energies Eps of their $EF(E)$spectra. Furthermore, more distant GRBs appear to be systematically harder in the X–ray band compared to GRBs with lower redshifts. We discuss how selection and data truncation effects could bias our results and give possible explanations for the correlations that we found.

We report on ASCAand BeppoSAXX–ray broad band observations of the galactic low-luminosity X–ray source 4U 1700+24 performed on 1995 and 1998, respectively, and on (quasi-)simultaneous ground observations of its optical counterpart, V934 Her, from the Loiano 1.5-meter telescope. In order to better understand the nature of the source we also analyze public archival ROSATand RXTEdata as well as the RXTEASM light curve of 4U 1700+24; we also re–analyze a 1985 EXOSATpointing. The optical spectra are typical of a M2 III star; this allows us to determine a revised distance to the object of ~400 pc. While these spectra do not show either any spectral change between the two epochs or any peculiar feature apart from those observed in normal red giants, the spectroscopic measurements carried out in X–rays reveal a complex and long-term variable spectrum, with a clear soft excess. The X–ray spectral properties of the source are best described by a thermal Comptonization spectrum plus a soft energy (<1 keV) excess, which can be modeled in the form of a blackbody emission with $kT_{\rm BB} \sim$1 keV; the latter component is not detected at the lowest source flux levels. The ratio between the two components varies substantially with the source flux. The X–ray emission from the object appears to become harder as its luminosity increases: indeed, the RXTEdata acquired during an outburst occurred in October-November 1997 display a hard tail, detected up to 100 keV and modeled with a comptonizing cloud which is hotter and less opaque than that seen in the low intensity state. Apart from erratic shot-noise variability on timescales of tens to thousands of seconds, no significant properties (such as pulsations or QPOs) are found from the timing analysis of the X–ray light curves extracted from the observations presented here. With the new distance determination, the 2–10 keV X–ray luminosity range spanned in the considered observations lies between ~2$\times$1032and ~1$\times$1034erg s-1. All this information, combined with the findings by other authors, allows us to suggest that the scenario which best describes the object consists of a wide binary system in which a neutron star accretes matter from the wind of a M-type giant star. Implications of such a model are discussed.

We present the X- and γ-ray detection of GRB 990704 and the discovery and study of its X-ray afterglow, 1SAX J1219.5-0350. Two pointed BeppoSAX observations with the narrow field instruments were performed on this source, separated in time by one week. The decay of the X-ray flux within the first observation appears unusually slow, being best-fit by a power law with negative index $0.83 \pm 0.16$. Such a slow decay is consistent with the non-detection in our second observation, but its back-extrapolation to the time of the GRB largely underestimates the detected GRB X-ray prompt emission. In addition, the GRB prompt event shows, among the BeppoSAX-WFC detected sample, unprecedentedly high ratios of X- and gamma-ray peak fluxes (F2-10 keV/$F_{\rm 40-700 keV}\sim0.6$, and F2-26 keV/$F_{\rm 40-700 keV}\sim1.6$) and fluences (S2-10 keV/$S_{\rm 40-700 keV}\sim1.5$and S2-26 keV/$S_{\rm 40-700 keV}\sim2.8$), making it, among the BeppoSAX arcminute-localized GRBs, the closest to the recently discovered class of Fast X-ray Transients.

The GRB010222 optical and near-infrared (NIR) afterglow was monitored at the TNG and other Italian telescopes starting ~1 day after the high-energy prompt event. The BVRlight curves, which are the best sampled, are continuously steepening and can be described by two power laws, $f(t) \propto t^{-\alpha}$, of indices $\alpha_1 \sim$0.7 and $\alpha_2 \sim$1.3 before and after a break occurring at about 0.5 days after the GRB start time, respectively. This model accounts well also for the flux in the U, Iand Jbands, which are less well monitored. The temporal break appears to be achromatic. The two K-band points are not consistent with the above behaviour, and rather suggest a constant trend. A low-resolution optical spectrum has also been taken with TNG. In the optical spectrum we found three absorption systems at different redshifts (0.927, 1.155 and 1.475), the highest of which represents a lower limit to, and probably coincides with, the redshift of the GRB. The broad-band optical spectral energy distributions do not appear to vary with time, consistently with the achromatic behaviour of the light curves. We compare our measurements with different afterglow evolution scenarios and we find that they favor a transition from relativistic to non-relativistic conditions in the shock propagation.

We compare the prompt X-ray (2-10 keV) emission of GRB 990510 measured by the BeppoSAX Wide Field Cameras (WFC) during the burst to the X-ray afterglow detected by the BeppoSAX Narrow Field Instruments. A single power-law model for the afterglow, $f(t) \propto t^{-1.42}$, is ruled out. Provided the initial time of the afterglow is assumed to coincide with the last short pulse in the X-ray prompt event (i.e., 72 s after the GRB trigger time), the X-ray emission from ~80 to 105s after the GRB trigger is well described by an external shock expanding in a decelerating jet, in which synchrotron radiation takes place. This model, represented by a double power-law of indices $\alpha_1 \simeq 1$and $\alpha_2 \simeq 2$before and after a jet collimation break time of ~0.5 days after GRB, respectively, is consistent with the second and third upper limits measured by the WFC, but not with the first. This may be related to inhomogeneities in the circumburst medium. Our finding indicates that the temporal behavior of the GRB 990510 X-ray afterglow is similar to that at optical wavelengths, and thus strengthens the interpretation of the multiwavelength afterglow as synchrotron emission in a jet with decreasing Lorentz factor. GRB 990510 is thus the only burst in which evidence of a spreading jet has been found in X-rays.

Abstract: LOFT is a satellite mission currently in Assessment Phase for the ESA M3 selection. The payload is composed of the Large Area Detector (LAD), with 2–50 keV energy band, a peak effective area of about and an energy resolution better than 260 eV, and the Wide Field Monitor (WFM), a coded mask imager with a FOV of several steradians, an energy resolution of about 300 eV and a point source location accuracy of 1 arcmin in the 2–30 keV energy range. Based on preliminary considerations and estimates, we show how the scientific performances of the WFM are particularly suited to investigate the most relevant open issues in the study of GRBs: the physics of the prompt emission, the spectral absorption features by circum-burst material (and hence the nature of the progenitors), the population and properties of XRFs, and the detection and rate of high-z GRBs. Measurements of the early afterglow emission with the Large Area Detector (LAD) may also be possible depending on the mission slewing capabilities and TOO observations policy. [Copyright &y& Elsevier]

Body mass index (BMI), serum cytokines and serum obesity markers were evaluated in 33 obese children before, during and after a hypocaloric diet. The cytometric bead array “human inflammatory kit” was used for the evaluation of serum interleukin (IL)-1, IL-6, IL-10 and tumor necrosis factor-... On the other hand, the following obesity biomarkers were evaluated by means of a flowcytomixhuman obesity 9 plex kit: Soluble Isoform of CD40 Ligand; Soluble Intercellular Adhesion Molecule-1; Leptin; Monocyte Chemoattractant Protein 1; Myeloperoxidase; Osteoprotegerin; Resistin and Soluble TNF-receptors. Actually, throughout the study modifications of BMI were negligible and, therefore, serum cytokines and obesity markers did not show any significant changes in comparison with baseline values. On the other hand, at the different time points considered the majority of obesity markers were higher than normal controls, thus indicating a low grade inflammation in childhood obesity. Therefore, attempts at reducing this inflammatory status in children which predisposes to the metabolic syndrome outcome are discussed.

In a group of 14 healthy aged subjects, donkey and goat milk was administered respectively, for a period of one month. Cytokine profile [interleukin (IL)-12, IL-10, IL-1, IL-8, IL-6 and Tumor Necrosis Factor (TNF)-] was assessed before and after milk intake by means of a cytometric bead array test. Data demonstrated that IL-12 was undetectable, while IL-10, IL-1 and TNF- were released in very low amounts. Quite interestingly, IL-8 was increased by donkey milk administration, while same cytokine was dramatically decreased following goat milk intake. Same pattern of response was noted with IL-6 even if levels of these cytokine were lower than those detectable in the case of IL-8. Taken together, these findings indicate that administration of donkey milk in the aged host is able to upregulate the immune response, while goat milk seems to reduce the exaggerated acute phase response in elderly.

Ten free-living elderly were administered with a synbiotic [fermented milk containing Lactobacillus rhamnosus Gorbach and Goldin (LGG®)] and oligofructose as a prebiotic for one month. Serum cytokines were evaluated before (T0) and after (T1) synbiotic administration. At T0, values of Interleukin (IL)-12, IL-6, IL-10, IL-1 and Tumor Necrosis Factor (TNF)- were lower than normal controls, with the exception of IL-8, thus confirming previous results on the impairment of both innate and adaptive responses in elderly. At T1, the synbiotic was able to significantly increase, depressed values of IL-1, IL-6 and IL-8 with a trend to a modest increase for the restant cytokines. In conclusion, the synbiotic used in this study seems to be very beneficial to elderly for its capacity to maintain the immune homeostasis, even if an increase in dosage and prolongation of administration time are required for a better modulation of the aged adaptive immune response.

The long and relatively faint gamma-ray burst GRB?060605 detected by Swift/BAT lasted about 20?s. Its afterglow could be observed with Swift/XRT for nearly?1?day, while Swift/UVOT could detect the afterglow during the first?6?h after the event. Here, we report on integral field spectroscopy of its afterglow performed with PMAS/PPak mounted at the Calar Alto?3.5?m telescope. In addition, we report on a detailed analysis of XRT and UVOT data and on the results of deep late-time VLT observations that reveal the GRB?host galaxy. We find that the burst occurred at a redshift of z = 3.773, possibly associated with a faint, RC= 26.4 ? 0.3 host. Based on the optical and X-ray data, we deduce information on the SED of the afterglow, the position of the cooling frequency in the SED, the nature of the circumburst environment, its collimation factor, and its energetics. We find that the GRB?fireball was expanding into a constant-density medium and that the explosion was collimated with a narrow half-opening angle of about?2.4?degrees. The initial Lorentz factor of the fireball was about?250; however, its beaming-corrected energy release in the gamma-ray band was comparably low. The optical, X-ray afterglow, on the other hand, was rather luminous. Finally, we find that the data are consistent within the error bars with an achromatic evolution of the afterglow during the suspected jet break time at about 0.27?days after the burst.

The origin, reliability, and dispersion of the Ep,i???Eisoand other spectral energy correlations is a highly debated topic in GRB?astrophysics. GRB?080916C, with its enormous radiated energy (Eiso?~ 1055?erg in the 1?keV-10?GeV cosmological rest-frame energy band) and its intense GeV?emission measured by Fermi, provides a unique opportunity to investigate this issue. In?our analysis, we also study another extremely energetic event, GRB?090323, more recently detected and localized by Fermi/LAT, whose radiated energy is comparable to that of GRB?080916C in the 1?keV-10?MeV energy range. Based on Konus/WIND and Fermi spectral measurements, we find that both events are fully consistent with the Ep,i???Eiso?correlation (updated to include 95?GRBs with the data available as of April?2009), thus further confirming and extending?it, and providing evidence against a possible flattening or increased dispersion at very high energies. This also suggests that the physics behind the emission of peculiarly bright and hard GRBs is the same as for medium-bright and soft-weak long events (XRFs), which all follow the correlation. In addition, we find that the normalization of the correlation obtained by considering these two GRBs and the other long ones for which Ep,i?was measured to high accuracy by the Fermi/GBM are fully consistent with those obtained by other instruments (e.g., BeppoSAX, Swift, Konus/WIND), thus indicating that the correlation is not affected significantly by ?data truncation? because of detector thresholds and limited energy bands. A?Fermi/GBM accurate estimate of the peak energy of a very bright and hard short GRB with a measured redshift, GRB?090510, provides robust evidence that short GRBs do not follow the Ep,i???Eiso?correlation and that the Ep,i???Eiso?plane can be used to discriminate between, and understand, the two classes of events. Prompted by the extension of the spectrum of GRB?080916C to several?GeV (in?the cosmological rest-frame) without any excess or cut-off, we also investigated whether the evaluation of Eisoin the commonly adopted 1?keV-10?MeV energy band may bias the Ep,i???Eiso?correlation and/or contribute to its scatter. By computing Eisofrom 1?keV to 10?GeV, the slope of the correlation becomes slightly flatter, while its dispersion does not change significantly. Finally, we find that GRB?080916C is also consistent with most of the other spectral energy correlations derived from?it, with the possible exception of the Ep,i???Eiso???tb?correlation.

Polyphenols contained in red wine possess a broad array of properties which seem to be beneficial to human and animal health. We have investigated the ability of red wine polyphenols to promote the in vitro release of both proinflammatory and antiinflammatory cytokines from human healthy mononuclear cells, as well as of immunoglobulins from B cells. Following red wine (Negroamaro) pretreatment of lymphomonocytes, results will show a production of regulatory [Interleukin( IL)-12], proinflammatory (IL-1 and IL-6), and anti-inflammatory (IL-10) cytokines, as well as of IgA and IgG. The fine balance between inflammation and antiinflammation, as well as the role of humoral immune response either systemic or mucosal will be discussed as a consequence of red wine intake. Finally, since ageing is characterized by a decline of many immune functions, our results suggest that moderate use of red wine may be beneficial in age-related disorders where the host immune response is very often not effective against a variety of antigens.

We examined the relationship between moderate obesity and glucose metabolism, insulin sensitivity and suspected fatty liver in children. We measured body mass index (BMI), z-score BMI, caliper skinfold thickness, waist and hip circumference in 94 participants (mean age 9.7 ±2.2 years). Fasting blood glucose, insulin, HOMA score, lipid profile and transaminases (ALT, AST) were measured. Fatty liver and skinfold thickness were evaluated by means of ultrasound. The z-score BMI was 2.01 ±0.39 (mean ± SD), and the duration of obesity was 4.3±3.03 years. A positive correlation was found between caliper and US skinfold thickness for tricipital (r 0.33; p 0.003) and sovrailiac skinfold (r 0.34; p0.003). Fatty liver was diagnosed in 64 of children and it was positively related to anthropometric measurements. The three sub-groups-group 0 (normal US liver and normal transaminases); group 1 (US fatty liver and normal transaminases); group 2 (US fatty liver and elevated transaminases)-showed a difference concerning z-score BMI, insulin and HOMA parameters (Tukey test: z score BMI group 1 vs group 0 and 2 vs group 0; serum insulin: group 2 vs group 1 and group 2 vs group 0; HOMA IR: group 2 vs group 1 and group 2 vs group 0). Moderately obese children with steatosis exhibited a clear increase of insulin and insulin resistance which represents indices of a future metabolic syndrome. In addition, it is important to perform a liver ultrasound since transaminases seems to be not adequate for the diagnosis of fatty liver.

Donkeys milk is the best substitute of human milk for its content in lactose, proteins, minerals, and -3 fatty acids. Here, we have evaluated the effects of colostrum and milk from donkeys (Martina Franca breed) on the function of human peripheral blood mononuclear cells (PBMCs) at different intervals from lactation. Colostrum induced more IgA responses, while milk induced predominantly more IgG responses. Both milk and colostrum induced expression of CD25 and CD69 on PBMCs. The ability to induce release of interleukins (IL) (IL-12, IL-1 and IL-10) and tumor necrosis factor- was confined only to milk, while colostrum was devoid of this capacity. Finally, both colostrum and milk induced nitric oxide (NO) release from PBMCs but milk exhibited a greater capacity than colostrum in NO generation. Taken together, these immunological activities exerted by both colostrum and milk from donkeys may be useful in the treatment of human immune-related diseases. In particular, NO induction by donkeys milk may be very useful in the prevention of atherosclerosis, being a strong vasodilator and an effective antimicrobial agent since pathogens and/or their products may play a proatherogenic role.

Hereditary Haemorrhagic Telangiectasia (HHT) or Rendu-Osler-Weber syndrome is an autosomal dominant disease characterized by local angiodysplasia affecting different organism districts. From a clinical viewpoint, HHT patients suffer from epistaxis, mucocutaneous telangiectases and arteriovenous malformations in various organs. Mutations in two known genes (ENG and ALK1) account for the majority of HHT patients. Additional loci are predicted, but the underlying genes are still to be identified. Moreover, SMAD4 mutations have been reported to cause JP-HHT combined syndrome. Both endoglin and ALK-1 bind to various growth factors in the context of the Transforming Growth Factors (TGF)- superfamily and their expression is restricted to vascular endothelial cells and very few other cell types, such as activated monocytes. Endoglin and ALK1 mutations are thought to affect endothelial cell metabolism, angiogenesis and vascular remodelling, even if the precise mechanism leading to the HHT lesions is still obscure. Endoglin is also overexpressed in smooth muscle cells of atherosclerotic plaques, suggesting a role for this protein in atherogenesis and plaque progression, as well as in other cardiovascular diseases. Recently, we demonstrated that HHT adult patients display several deficits of both innate and adaptive immune system. Here, we investigated the function of immune cells in HHT pediatric patients. Our results clearly show that HHT children have a normal functionally immune system, and suggest that HHT patients become immunocompromised host during their lifetime, likely due to a precocious immunosenescence. Moreover, the relationship between immune responsiveness in HHT and atherosclerosis are discussed.

Evidence has been provided that red wine possesses antiatherogenic activities in virtue of its content in polyphenols (flavonoids and non-flavonoids substances). Here, some red wines (Negroamaro, Primitivo and Lambrusco) were tested for their ability to trigger nitric oxide (NO) production from human healthy peripheral blood mononuclear cells (PBMC). Negroamaro was the strongest inducer of NO from PBMC and deprivation of polyphenols did not influence its NO generation capacity. This fact supports the involvement of polyphenols in the NO production even in the absence of alcohol, which also per se does not exert any significant activity. These results are also corroborated by the evidence that PBMC inducible-nitric oxide synthase expression occured by the effect of samples containing polyphenols but this expression was very weak when polyphenols were removed from the whole Negroamaro. In synthesis, flavonoids and resveratrol, major constitutents of red wine, once absorbed at intestinal level, enter circulation and trigger monocytes for NO production. To the best of our knowledge, this is the first demonstration of a direct effect of red wine on monocytes for NO release to occur. On the other hand, also the macrophage contingent from gut-associated lymphoid tissue can contribute to NO generation, besides the aliquot produced by endothelial cells, as previously demonstrated by various authors. Taken together, these results support the concept that moderate intake of red wine can prevent atherosclerosis via production of NO, a potent vasodilator of terminal vessels.

Hereditary hemorrhagic telangiectasia (HHT) is characterized by vessel alterations such as dilatation of postcapillary venules and arterio-venous communications, which account for the major clinical manifestations of the disease. Two types of HHT have been characterized HHT-1 and HHT-2, respectively, depending the former on endoglin mutations and the latter on activin receptor-like kinase 1 (ALK-1) mutations. Both endoglin and ALK-1 bind to the transforming growth factor (TGF) superfamily which, physiologically, regulates the activities of endothelial cells and also those related to the extracellular matrix. In this review, the salient features of TGF- will be outlined with special reference to its activity on the immune system and on tumorigenesis. Furthermore, the involvement of TGF- in the pathogenesis of some gastrointestinal diseases will be discussed and, in particular, in the course of liver disease, Helicobacter pylori infection and inflammatory bowel disease. In the light of these data and of animal model of HHT, the potential risk of developing other diseases in HHT patients will be discussed.

Experimental evidences on the adaptive immune response in patients with hereditary hemorragic telagiectasia (HHT) are lacking. Here, we report in 9 patients with HHT a multiple deficit involving the intracellular expression of T helper (h)1-derived cytokines [Interferon (IFN)-, Interleukin (IL)-2 and Tumor Necrosis Factor (TNF)-] and of monocyte- derived TNF-. On the other hand, percentages of Th2-derived cytokines (IL-4, IL-5 and IL-10) were normal or, in some cases, above normality. Quite interestingly, monocyte-derived IL-10 was detectable in 5 out of 9 patients in a percentage of cells comparable to controls or exceeding normal levels. Taken together, these data point out, in HHT, an ablation of Th1-responses, while Th2-type cytokines are preserved, thus exerting either a suppressive effect on Th1-cells (via IL-4 and IL-10) or an antiinflammatory response on monocyte-derived TNF- (via IL-10). Furthermore, monocytederived IL-10 may also contribute to the antiinflammatory activity seen in HHT. According to current literature even if patients with HHT do not exhibit certain diseases, such as autoimmune diseases, cancer and abnormal responses to pathogens, the observed immune deficits need to be diagnosed and therapeutically corrected.

Experimental evidences on the adaptive immune response in patients with hereditary hemorragic telagiectasia (HHT) are lacking. Here, we report in 9 patients with HHT a multiple deficit involving the intracellular expression of T helper (h)1-derived cytokines [Interferon (IFN)-γ, Interleukin (IL)-2 and Tumor Necrosis Factor (TNF)-α] and of monocyte- derived TNF-α. On the other hand, percentages of Th2-derived cytokines (IL-4, IL-5 and IL-10) were normal or, in some cases, above normality. Quite interestingly, monocyte-derived IL-10 was detectable in 5 out of 9 patients in a percentage of cells comparable to controls or exceeding normal levels. Taken together, these data point out, in HHT, an ablation of Th1-responses, while Th2-type cytokines are preserved, thus exerting either a suppressive effect on Th1-cells (via IL-4 and IL-10) or an antiinflammatory response on monocyte-derived TNF-α (via IL-10). Furthermore, monocytederived IL-10 may also contribute to the antiinflammatory activity seen in HHT. According to current literature even if patients with HHT do not exhibit certain diseases, such as autoimmune diseases, cancer and abnormal responses to pathogens, the observed immune deficits need to be diagnosed and therapeutically corrected.

Hereditary hemorrhagic telangiectasia (HHT) is characterized by vessel alterations such as dilatation of postcapillary venules and arterio-venous communications, which account for the major clinical manifestations of the disease. Two types of HHT have been characterized HHT-1 and HHT-2, respectively, depending the former on endoglin mutations and the latter on activin receptor-like kinase 1 (ALK-1) mutations. Both endoglin and ALK-1 bind to the transforming growth factor (TGF) superfamily which, physiologically, regulates the activities of endothelial cells and also those related to the extracellular matrix. In this review, the salient features of TGF-β will be outlined with special reference to its activity on the immune system and on tumorigenesis. Furthermore, the involvement of TGF-β in the pathogenesis of some gastrointestinal diseases will be discussed and, in particular, in the course of liver disease, Helicobacter pylori infection and inflammatory bowel disease. In the light of these data and of animal model of HHT, the potential risk of developing other diseases in HHT patients will be discussed.

In healthy individuals, natural and adaptive immune responses are able to control virus entry into the host. In particular, CD8-mediated cytotoxicity, sustained by the intervention of CD4 cells, represents the major key event leading to virus eradication. On the other hand, viruses are able to evade from host immune response via several mechanisms, and special emphasis will be placed on hepatitis C virus and chronic Epstein-Barr infections also in view of personal data. Virokines, viroreceptors, and serpins greatly contribute to viral immune escape, and, among virokines, interleukin (IL)-10 has been object of intensive studies. Finally, all these products have been used as biopharmaceuticals, and, for instance, viral IL-10, chemokine-binding proteins, and serpins exhibit in animal models immunosuppressive, antiinflammatory, and antiatherogenic activities. As far as their use in human trials is concernded, many cautions are required in order to avoid deleterious side effects and, in particular, the purity of the product, its route and frequency of administration, as well as the immune status of the patient should be taken into serious account.

The scintillator counters of the TOF system of AMS-02 is beeing constructed to match the needs of the AMS-02 experiment that is armed by a high aperture superconducting dipole magnet. The goals of the TOF-02 hodoscopes actually are: to give the fast trigger to the all sub-detectors of AMS-02; to measure the particle velocity ensuring a albedo rejection; to measure the absolute charge by particle energy loss, up to at least . In spring of 2005 all the TOF counter planes will be assembled and the space qualification tests will be performed. A description of the first test results and of the TOF performances will be given. [Copyright &y& Elsevier]

Abstract: A review of the HAXTEL project devoted to the development of a Laue lens telescope for hard X-/gamma-ray observation of the continuum spectra of celestial sources is presented. Main design properties, open issues, the status of the project and an example of multi-lens configuration with sensitivity expectations are discussed.

β-glucans (BG) are polysaccharides contained in the cell wall of fungi but also present in nature as normal constituents of oats, barley and yeast. The recent discovery of the major receptor for BG on antigen-presenting cells, dectin-1, has given a strong impetus to a series of researches on BG immunobiological activities. In particular, BG possess antimicrobial activity by exerting a direct effect on monocytes and neutrophils. At the same time, BG-induced removal of inflammatory cells from infectious foci and suppression of proinflammatory cytokines support the antiinflammatory ability of this molecule. BG have been detected in serum of patients with fungal infections and hepatitis C virus infection by means of the Limulus amebocyte lysate assay. Data suggest the antiinflammatory role of BG in these patients, even if the exact nature of circulating BG is still unknown. Of note, clinical trials in patients with postsurgical infections, sepsis and trauma have been conducted by administration of BG in alternative to corticosteroid and anti-cytokine monoclonal antibody (MoAb) therapy which give rise to more serious side effects. As far as anticancer activity of BG is concerned, evidence has been provided that BG behave as an adjuvant for MoAb therapy against tumors. In fact, in a murine model, it was demonstrated that granulocytes with BG bound to CR3 could kill iC3b coated tumor cells, thus potentiating the tumoricidal activity of MoAbs. Taken together, these studies seem to support a beneficial role of BG in the host, even if the exact mechanisms of action of this molecule on the immune network deserves furter elucidation.

Previous data demonstrated that an elevated percentage of hepatitis C virus (HCV) infected patients are endotoxemic. Endotoxemic patients are poor responders to the interferon (IFN)- / ribavirin (RIB) treatment and exhibit lower serum levels of IFN- and interleukin (IL)-10 than the responder counterpart. Here we provide evidence that in endotoxemic HCV patients absolute numbers of CD19 cells (B cells) are higher than those observed in the non-endotoxemic counterpart at the end of the combined treatment. Moreover, anti lactoferrin (LF) antibodies are more elevated in non-responder HCV patients than in the responders. In turn, these autoantibodies may affect the antiviral activity of LF, on the one hand , and, on the other hand abrogate the LF binding to lipopolysaccharides (LPS). Such an interaction hampers the binding of LPS to LPS binding protein, thus inhibiting LPS fixation to CD14 cells and, ultimately, leading to a decreased release of proinflammatory cytokines.